This article came up while I was catching up on my gmail account.
It was not until two decades ago that archaeologists arrived at an explanation that most now accept: the Chaco people built the Great House as a lunar observatory precisely aligned to a celestial event that occurs just once in a generation.
That rare event, a “major lunar standstill,” is happening now, and continues through 2007. To witness this extraordinary moonrise, some two dozen visitors, including me, arrived to climb the Chimney Rock mesa in the middle of an August night.
Every 18.6 years, the moon does something strange: it radically expands the voyage it makes each month across the sky and, at the northern and southernmost edges of that journey, appears to rise in the same spot for two or three nights in a row.
I am fascinated at some of the things civilizations knew about the night sky. The Chaco figured out that if you were in a particular spot during the full moon every 18.6 years you could see this particular phenomenon. Other civilizations had figured out similar things, and each time I learn about them I’m in awe of what they knew.
I think that’s part of the reason I keep looking up at night, even if I can’t see much with the lights from the city. Some day I’ll make it out to one of the CAS meetings…but not this month…this month’s meeting takes place on October 14th, when Luc and I will be at the TulsaTechFest.